/* Basic reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html, body {
  height: 100%;
  width: 100%;
  background-color: #000;
  font-family: 'Arial', sans-serif;
}

/* Centered iframe container */
.flipbook-container {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  width: 100%;
  overflow: hidden;
  background: #111;
}

/* Responsive iframe */
.flipbook-container iframe {
  width: 100%;
  height: 100%;
  border: none;
  max-width: 1400px;
  box-shadow: 0 0 20px rgba(0,0,0,0.3);
}